Typewriting machine



Jan. 14-, AVERY -TYPEWRITING MACHINE Filed Jan. 15, 1932* 2 Sheets-Sheet l INVENTOR H EN RY A. AVERY ATTORNEYS Jan. 14, 1936. H. A. AVERY TYPEWRITING MACHINE Filed Jan. 15, 1932 2 Sheets-Sheet 2 HEN RY A.AVERY Patented Jan. 14, 1936 UNITED STATES PATENT OFFICE TYPEWRITING MACHINE Application January 15, 1932, Serial No. 586,724

6 Claims.

This invention relates to improvements in typewriting machines, and more particularly to improvements in inking ribbon actuating mechanism of such machines.

The invention provides a ribbon actuating mechanism for feeding a ribbon, manually and automatically reversing the direction of feed of the ribbon, and. for vibrating the ribbon edgewise different extents and preventing such edgewise vibration of the ribbon, which mechanism is characterized by simplicity of construction and positiveness of operation. The invention also porvides a ribbon mechanism especially adapted for embodiment in small and low portable type writing machines with marked space limitations for a ribbon actuating mechanism having the aforesaid functions.

In the drawings, in which so much of a portable typewriter of low height is shown as is necessary for an understanding of the invention,

Fig. l is a fragmentary perspective View of the machine with the several operating parts in idle position;

Fig. 2 is a detail front elevation of part of the ribbon vibrating means adjusted for stencil typing operation of the machine;

Fig. 3 is a front elevation of part of the ribbon actuating mechanism adjacent the left hand side of the machine, some parts being shown in vertical transverse section, and the axially shifted shaft being shifted fully to the left from the position shown in Fig. 1;

Fig. l is a top plan view of the parts as shown in Fig. 3;

Fig. 5 is a fragmentary view of the ribbon mechanism in front elevation showing the parts at the end ofa ribbon feed reversing operation in which the axially shiftable gear shaft is shifted fully to the right from the position thereof shown in'Figs. 3 and 4 into the position of the gear shaft shown in Fig. 1;

Fig. 6 is a vertical sectional view on the line 6-6 of Fig. 3;-

Fig. '7 is a sectional view similar to Fig. 6 showing the position of the feed pawl and pawl carrier at the end of the down stroke of a type key; and

Fig. 8 is a detail vertical sectional view on the line 8-8 of Fig. 5, the parts in Figs. 5 and 8 being positioned as at the end of the down stroke of a type key following exhaustion or substantial exhaustion of the ribbon from the right hand ribbon spool.

The machine, only so much of which is shown as is necessary to understand the construction and operation of the ribbon actuating mechanism, has a fixed or rigid frame-work of low height on which are mounted the ribbon mechanism and other moving parts of the machine, such as the platen carriage (not shown), parts of this framework being shown in the drawings and designated by the reference numeral Ill, and a part of the platen being shown at H.

The inking ribbon I2 is wound from one to the other of two ribbon spools l3 forward of the platen, which spools are held on the upper ends of two vertical spool carrying shafts l4 journalled in framework In adjacent opposite sides of the machine and extending close to the bottom of the framework. Each shaft I 4 has a bevel gear l5 fixed on its lower end. A horizontal shaft [6 extends transversely of the machine and is journalled and endwisely slidable in fixed bearings I! on the frame adjacent its ends. Each end of shaft I 6 has a bevel gear l8 fixed thereon, the shaft being shiftable endwisely to mesh one gear 18 with one of the gears l5 and simultaneously demesh the other gear ill from the remaining gear l5.

Drive shaft i6 has aratchet wheel I9 fixed thereon the hub of which protrudes beyond both faces of the wheel and is formed at its left hand end with an annular double-bevel cam rib 29; The shaft is actuated both rotatively and endwisely by a rocking actuating member 2| in the U form of a pawl carrier of yoke form, the arms of which extend down from the cross-bar of the yoke and engage against opposite ends of the ratchet wheel hub and turn about shaft it which passes loosely through bearing apertures in the arms.

The driving pawl 22 of the ribbon feeding mechanism is of bail-like form and mounted in the upper part of the yoke with its side arms pivoted at 23 to the side arms of the yoke and abutted against the yoke arms and extending rearward to. the cross-bar of the bail-like pawl, which cross-bar is formed with a pendent nose held in engagement with the teeth of the ratchet wheel by a spring 24 connecting the pawl and pawl carrier. Reverse rotation of the ratchet wheel is prevented by a flat fore and aft extending spring detent 25 held to the machine frame at one end at 26 and provided with a wide longitudinal slot 21 across which the ratchet wheel shifts when shaft i6 is slid endwise, the teeth of the ratchet wheel engaging with the rear transverse edge of this detent slot.

The actuating member or pawl carrier 2| is vibrated fore and aft to the machine at the strokes of the type keys, to rotate the drive shaft on the up strokes of the keys, through the medium of the universal bar 28 operated by a part of each type action. One of the type ac-- tions is shown, comprising a type key 29 connected by suitable linkage to actuate a rearwardly swinging type bar 30, one element of the linkage having a lug 2| for depressing the universal bar on the down stroke of the key. The universal bar has forwardly extending arms journalled on horizontal pivots S2 at opposite sides of the frame, one of which arms normally engages under a stop 33 on the frame.

The universal bar is forward of shaft l6, and. the universal bar has a pendent extension 34 adjacent its fulcrum connected by a fore and aft extending link 35 to an upwardly extending rock arm 38 fixed on the left hand end of a horizontal rock shaft 3! and having a forward extension connected to the framework E0 by a return spring 38 for the ribbon mechanism and universal bar. Rock shaft 3? has a fore and aft swinging rock arm E39 extending upward therefrom, which arm is connected by a link 40 to the upstanding pawl carrier 2| on the drive shaft to rock said carrier forward on the down stroke of the key and rearward on the return stroke of the key, pawl 22 rotating the ratchet on the return or rearward stroke of the pawl carrier. Shaft 3'! extends transversely of the machine from the left hand side to about the medial vertical plane of the machine and is journalled in the framework at its ends.

In Figs. 1 and 5 the endwisely slidable drive shaft is shown connected with the right hand spool shaft to drive the right hand ribbon spool for feeding the ribbon in one direction, and in Figs. 3 and 4 the drive shaft is shown connected with the left hand spool shaft to drive the left hand spool for feeding the ribbon in the opposite direction. The shaft It may be manually shifted endwise to reverse the ribbon feed at will, by rocking the forwardly extending handle arm of a bellcrank hand lever 4| mounted on the frame on a horizontal transversely extending pivot :32 and having its pendent arm engaged in the forked end of the transversely extending arm of the pawl-carrier sliding bellcrank lever 43. Lever 43 is mounted on a vertical pivot 44 in the frame and has arearwardly extending arm the forked rear end of which engages the opposite inner faces of the side arms of the pawl carrier 2| to force the carrier axially transversely of the machine toward the right when the handle arm of lever 4| is depressed and. toward the left when said handle arm is pulled upward.

The shaft I6 is yieldably latched in each shifted position by a horizontally swinging detent 45 pivoted at as on the frame and having a double beveled nose for yieldably engaging one or the other beveled side faces of the double beveled cam rib 20 on the hub of ratchet wheel |9 under the tension of spring 41 connecting the detent with the machine framework.

The ribbon |2 is provided adjacent each end with one of the usual pair of eyelets or projections 48 for setting an automatic ribbon feed reversing mechanism to effect automatic reversal of the ribbon upon exhaustion or substantial exhaustion of the ribbon from either spool. Each eyelet :38 is engageable with the upper end of a pair of upstanding control or trip levers 49 rockable transversely of the machine on horizontal fore and aft extending pivots 50 on the frame upon which pivots they have double bearings as shown. Each lever 49 has a longitudinal slot 5| in its upper end through which the ribbon passes, the slots in the levers being too narrow for passage of the ribbon eyelets, and each lever extending down from the inner edge of a difierent one of the spools and being pivoted near the adjacent side of the machine.

The levers 49 are pivoted about midway their ends, the pendent arm of each lever being constantly urged inward toward the center of the machine by a spring 52 connecting the upper arm of the lever with the frame, the levers normally standing upright with their lower ends connected with the pendent arms of different ones of a pair of ribbon reversing cams in the form of bellcrank levers 53 and holding the other or camming arms of these cam levers up in inactive position against a stop 54 formed on part of the machine frame ID.

The cam levers 53 are mounted on the frame on parallel for-and-aft extending horizontal pivots 55 located at a higher level than drive shaft IS, the pendent arms of the levers being seaced from the outer sides of yoke 2|, with the lower end of the left hand trip lever normally pressed against the outer edge of a forwardly extending lug on the lower end of the pendent arm of the left hand cam lever, and with the inner hook and of a horizontal transversely extending link 59 normally pressed against the left hand end of a horizontal transversely extending slot in the lower end of the pendent arm of the right hand cam lever. The outer or right hand end of link 55 is pivotally held to the lower end of the right hand trip lever.

The cam arms of bellcrank levers 53 converge toward each other and are oblique to drive shaft l6 and the path of rocking motion of the upper end of pawl-carrying yoke 2|, the cam arms being constantly urged downward by spring 56 connecting the cams above their pivots, into the paths of motion of two cam portions 51 of the pawl carrier formed by cutting a V-shaped notch in upper horizontal cross-bar of the yoke 2|. Two horizontal stop fingers 58 on the frame are engageable by the cam arms of the cam levers to arrest each of said arms with the arm extending oblique to shaft I6 in a horizontal plane.

With the shaft |5 connected for driving the left hand spool as in Figs. 3 and 4 to wind the ribbon on the left hand spool, when the ribbon is fully or substantially fully unwound or exhausted from the right hand spool, the ribbon eyelet 48 near the right hand end of the ribbon engages and. rocks right hand lever 49, and the right cam lever 53 is thus freed to rock into active position, whereupon on the next type key stroke thereafter the right hand cam portion 51 of the pawl carrier strikes the rear inclined face of the cam a m of the freed cam lever as the type key is depressed and the pawl carrier rocks forward, so that during completion of the forward stroke of the pawl carrier said carrier is cammed axially toward the right hand side of the machine (as shown in Figs. 5 and 8) until shaft I6 is moved endwise to the right into the position shown in 1, 5 and 8 to connect the shaft to drive the right hand spool and disconnect it from the left hand spool.

When the ribbon is exhausted from the left hand spool the shaft is shifted to the left into the position shown in Figs. 3 and 4 by rocking of the left hand lever 49 by the other ribbon eyelet, thereby freeing left hand cam lever 53 for engagement by left hand cam portion 51 of the pawl carrier to cam the carrier and shaft 56 to the left. The thrust connections of levers 49 with cam levers 53 permit either lever 49 to continue to rock under pull of the ribbon to avoid ribbon strain or tying up of the machine in cases in which a freed lever 53 drops down on top of the pawl carrier. In such cases, the freed lever drops in front of the pawl carrier as the carrier moves back, and cams the carrier axially on the next forward stroke of the carrier.

The ribbon I2 passes through the upper end of the usual up and down shiftable ribbon guide 60 which is shifted to carry the ribbon edgewise up over the printing point on platen I l on the down strokes of the keys and retract it from over said point on the return strokes of the keys. According to the present invention the ribbon is vibrated up and down by a ribbon vibrating device comprising said guide 60 and a bellcrank lever 6! having a forwardly extending arm to which the lower end of the guide is pivoted on a horizontal transverse pivot 62 and a pendent arm having two horizontal pins 63 extending toward different sides of the machine at different sides of the machine at different distances from the lever axis.

The lever (H is pivoted on the frame at 64 to rock about a horizontal transverse axis at a higher level than rock shaft 31 and is operated from said shaft by a fore-and-aft rocking actuator in the form of a yoke 65 having upwardly extending parallel arms loosely pivoted on shaft 31 for turning about said shaft and sliding axially on the shaft. Each upstanding arm of yoke 65 has a longitudinal slot 66 in its upper end, the slotted arms being located at opposite sides of the pendent arm of bellcrank lever Bl for reception of one pin 63 in the slot 66 of one arm and reception of the other pin 63 in slot 66 of the other arm to connect the actuator or yoke member 65 to the lever for rocking the lever.

The actuator yoke 65 is axially slidable on the shaft between two fixed limits by manually operable means comprising a bellcrank hand lever 61 pivoted on the frame at the right hand side of the machine on a horizontal transverse pivot '68, with its movement limited by engagement of its forwardly extending handle arm with the ends of a vertical slot 69 in a part of the frame.

Lever 61 has a pendent arm connected by a rearwardly extending link 18 to the rightwardly extending arm of a horizontally swinging bellcrank lever pivoted at H on the frame and provided with a rearwardly extending arm connected by a horizontal transversely extending l nk If! with actuator yoke 65. The handle arm of lever 61 is a laterally springy arm latchable in either of two notches in one vertical wall of slot 59 at opposite ends of slot 69, or in a medial notch in said slot wall, the three notches being designated 13.

A rock arm 14 f xed on rock shaft 31 has a horizontal projection 15, extending longitudinally of the rock shaft, slidably engaged in an aperture It in one upstanding arm of actuatorv yoke 65 between the upper end of said arm and the shaft 3! to key said yoke to the shaft to rock with the shaft except when the yoke is slid midway between the limits of its sliding motion by latching of the handle arm of lever 61 in the medial one of the three notches 13.

In this slidably adjusted medial position of the yoke a notch 11 in the forward edge of projection is opposite the rearwardly facing edge of aperture 16 in the apertured yoke arm, this notch being of sufficient depth to permit shaft 3'! to be rocked without rocking the yoke.

,The spacing of the slottted yoke arms is such that in the medially adjusted position of the yoke both pins 63 are engaged in the yoke arm slots 66 while, when the hand lever 67 is shifted to its upward limit the leftwardly extending pin 63 only is engaged with the yoke, and when the lever 67 is shifted to its downward limit only the rightwardly extending pin 63 is engaged with the yoke.

There is thus a constantly maintained mechanical connection between the shaft 3'! and the ribbon guide, the rock arm 14 being always interlocked with the yoke, and the yoke being always interlocked with the ribbon guide vibrating bellcrank, but in the medially adjusted position of the yoke the rocking of the shaft does not vibrate the ribbon. When the left hand pin alone is engaged in a yoke arm slot the ribbon has a. greater upward throw than when the right hand pin alone is engaged in a yoke arm slot, the ribbon remaining in lowered position to permit typing of stencils when both pins are engaged in the slots of the yoke arms.

Certain improvements disclosed but not claimed herein, which improvements relate particularly to ribbon vibrating means, constitute the subject matter of a divisional application filed by applicant February 26, 1935, and serially numbered 8,245.

What I claim is:

1. In a typewriting machine having an inking ribbon actuating mechanism of the kind in which a drive shaft is endwisely shifted to connect it alternately with two ribbon spool carrying shafts to feed the ribbon in either of two directions, the combination with the endwisely shiftable drive shaft of a ratchet wheel fixed to said shaft to turn and shift therewith, a pawl carrier mounted on said shaft to rock thereon and to shift the shaft endwise, a pawl carried by said pawl carrier and engaged with the ratchet wheel to turn the drive shaft in one direction when the pawl carrier is rocked on the shaft, and means for shifting the pawl carrier axially in opposite directions to move the shaft endwise and thereby control the direction of feed of the ribbon.

2. In a typewriting machine having an inking ribbon actuating mechanism of the kind in which a drive shaft is endwisely shifted to connect it alternately with two ribbon spool carrying shafts to feed the ribbon in either of two directions, the combination with the endwisely shiftable drive shaft of a ratchet wheel fixed to said shaft to turn and shift therewith, a pawl carrier mounted on said shaft to rock thereon and shift the shaft endwise, a pawl carried by said pawl carrier and engaged with the ratchet wheel to turn the drive shaft in one direction when the pawl carrier is rocked on the shaft, a ribbon feed reversing hand lever pivoted to rock about an axis parallel with the drive shaft, and a second lever pivoted to rock about an axis perpendicular to the drive shaft and having one arm engaged with the hand lever and a second arm engaged with the pawl carrier for shifting the carrier axially in both directions to determine the direction of feed of the ribbon by the pawl and ratchet wheel.

3. In a typewriting machine having an inking ribbon actuating mechanism of the kind in which a drive shaft is endwisely shifted to connect it alternately with two ribbon spool carrying shafts to feed the ribbon in either of two directions, the combination with the endwisely shiftable drive shaft of a ratchet wheel fixed to said shaft to turn and shift therewith, a pawl carrier mounted on said shaft to rock thereon and shift the shaft endwise, a pawl carried by said pawl carrier and engaged with the ratchet wheel to turn the drive shaft in one direction when the pawl carrier is rocked on the shaft, a pair of cams pivoted on fixed pivots and having oppositely inclined cam portions oblique to the drive shaft, said cams being spring urged about their pivots to position said inclined portions for engagement by the pawl carrier, a pair of spring-retracted levers each connected with a different one of said cams to normally hold its connected cam out of the path of rocking movement of the pawl carrier and each rockable by a projection on the ribbon to free its connected cam for interposition of the inclined cam portion thereof in the path of rocking movement of the pawl carrier to cam the carrier axially to automatically change the direction of feed of the ribbon when the carrier is rocked against the interposed cam portion of the freed cam.

4. In a typing machine wherein an inking ribbon is attached to a pair of spools at opposite sides of the machine operatively connected one at a time with a common drive shaft extending transversely of the machine by shifting the shaft endwisely in bearings on the main frame of the machine, the combination with said frame and shaft of a pawl carrying yoke loosely pivoted on said shaft, a pawl carried by said yoke, a ratchet wheel driven by said pawl rigidly held to the shaft and straddled by said yoke so as to hold the yoke and shaft and wheel against relative axial movement, type key actuated means for rocking the yoke on said shaft to rotate the ratchet wheel and shaft, and means for shifting the yoke transversely of the machine in both directions to shift the shaft endwise to drive different ones of the spools.

5. In a typing machine wherein an inking ribbon is attached to a pair of spools at opposite sides of the machine operatively connected one at a time with a common drive shaft extending transversely of the machine by shifting the shaft endwisely in bearings on the main frame of the machine, the combination with said frame and shaft of a pawl carrying yoke loosely pivoted on said shaft, a pawl carried by said yoke, a ratchet wheel driven by said pawl rigidly held to the shaft and straddled by said yoke so as to hold the yoke and shaft and wheel against relative axial movement, type key actuated means for rocking the yoke on said shaft to rotate the ratchet wheel and shaft, a pair of cams pivoted on the main frame to swing about axes perpendicular to said shaft, and each having a cam surface oblique to said shaft, the cam surfaces of said two cams being oppositely inclined to the shaft and the cams being connected by a spring constantly tending to swing said cams on their pivots to interpose said cam surfaces in the field of rocking motion of said yoke, a pair of springretracted levers pivoted on the frame and each connected with a different one of said cams to normally hold said cam surfaces out of the field of rocking motion of the yoke and each rockable by a different projection on the ink ribbon to release its connected cam, and means for arresting swinging movement of each of said cams in two positions in one of which the yoke is free to rock without engaging the cam and in the other of which the yoke as it rocks strikes the oblique cam surface of the cam and is deflected transversely of the machine to shift the shaft endwise and thereby reverse the direction of ribbon feed.

6. In a typewriting machine having an inking ribbon actuating mechanism of the kind wherein a drive shaft is endwisely shiftable to connect it alternately with two ribbon spools to feed the ribbon in either of two directions, the combination with said shaft of a ratchet wheel fixed to the shaft to turn and shift therewith, a pawl carrier mounted on said shaft to rock thereon and to shift the shaft endwise, a pawl carried by said carrier and engaged with the ratchet wheel to turn the shaft in one direction when the carrier is rocked on the shaft, means for shifting the carrier axially in opposite directions to move the shaft endwise and thereby control the direction of ribbon feed, a rock shaft parallel to said first-mentioned shaft, a rock arm fixed on the rock shaft and connected to the carrier to oscillate the carrier, and a universal bar actuated at the type key strokes of the machine and connected to the rock shaft to oscillate the latter.

HENRY A. AVERY. 

